13 research outputs found
INFLUENCE OF DIFFERENT BLEACHING SYSTEMS ON THE BOND STRENGTH OF LAMINATE VENEER TO ENAMEL
Purpose: The objective of this in-vitro study was to examine the microtensile bond strength of a porcelain laminate veneer (PLV) to tooth surface bleached with photoactivation by blue light-emitting diode (LED) or diode laser. Methods: Eigthteen extracted human central incisors were randomly divided into three groups. Two sticks were obtained from each tooth (n=12). Before surface treatments; teeth were prepared to provide space for PLVs. The first group teeth were bleached with Whiteness HP which is contain 35% hydrogen peroxide (HP) and then photoactivated with a LED for 20 seconds. The second group were bleached with Laserwhite 20 which is contain 46% HP and photoactivated with a diode laser for 30 seconds. The third group received no surface treatment and served as the control group. IPS Esthetic ceramic veneers were luted with Variolink II veneer cement . The teeth were sectioned to obtain porcelain-resin-enamel/dentin sticks and submitted to a MTB testing device. The maximum load at fracture was recorded. Data were analyzed using one-way ANOVA followed by the Tukey HSD post-hoc test at a preset α of 0.05. Results: One-way ANOVA revealed that there was significant difference between LED unit group and control group (p<.05) but no statistical differences were observed with diode laser group (p>.05) The LED unit group presented significantly lower bond strength value (6.49±2.3 MPa) than diode laser (8.49 ±3.1 MPa) and control groups (9.53±2.7 MPa). Conclusion: The results suggested that bleaching therapy with activation by LED or diode laser reduced the bond strength of IPS Esthetic ceramic veneers to tooth surfaces.
Keywords: Teeth Bleaching; Photoactivation; Semiconductor lasers; Diode laser; Microtensile
INFLUENCE OF DIFFERENT BLEACHING SYSTEMS ON THE BOND STRENGTH OF LAMINATE VENEER TO ENAMEL
Purpose: The objective of this in-vitro study was to examine the microtensile bond strength of a porcelain laminate veneer (PLV) to tooth surface bleached with photoactivation by blue light-emitting diode (LED) or diode laser. Methods: Eigthteen extracted human central incisors were randomly divided into three groups. Two sticks were obtained from each tooth (n=12). Before surface treatments; teeth were prepared to provide space for PLVs. The first group teeth were bleached with Whiteness HP which is contain 35% hydrogen peroxide (HP) and then photoactivated with a LED for 20 seconds. The second group were bleached with Laserwhite 20 which is contain 46% HP and photoactivated with a diode laser for 30 seconds. The third group received no surface treatment and served as the control group. IPS Esthetic ceramic veneers were luted with Variolink II veneer cement . The teeth were sectioned to obtain porcelain-resin-enamel/dentin sticks and submitted to a MTB testing device. The maximum load at fracture was recorded. Data were analyzed using one-way ANOVA followed by the Tukey HSD post-hoc test at a preset α of 0.05. Results: One-way ANOVA revealed that there was significant difference between LED unit group and control group (p<.05) but no statistical differences were observed with diode laser group (p>.05) The LED unit group presented significantly lower bond strength value (6.49±2.3 MPa) than diode laser (8.49 ±3.1 MPa) and control groups (9.53±2.7 MPa). Conclusion: The results suggested that bleaching therapy with activation by LED or diode laser reduced the bond strength of IPS Esthetic ceramic veneers to tooth surfaces.
Keywords: Teeth Bleaching; Photoactivation; Semiconductor lasers; Diode laser; Microtensile
Analysis of various potential prognostic markers and survival data in clear cell renal cell carcinoma
ABSTRACT Purpose Clear cell renal cell cancers frequently harbor Von Hippel-Lindau gene mutations, leading to stabilization of the hypoxia-inducible factors (HIFs) and their target genes. In this study, we investigated the relationship between vascular endothelial growth factor (VEGF), HIF-1α, HIF-2α, p53 positivity, microvessel density, and Ki-67 rates with prognostic histopathologic factors (Fuhrman nuclear grade, stage, and sarcomatoid differentiation) and survival in clear cell renal cell carcinomas. Material and Methods Seventy-two nephrectomy specimens diagnosed as clear cell renal cell carcinoma between 2000 and 2012 were reevaluated. Immunohistochemically VEGF, HIF-1α, HIF-2α, p53, CD34 (for microvessel density evaluation), and Ki-67 antibodies were applied to the tumor areas. The relationships of these antibodies with prognostic factors and survival rates were evaluated with statistical analyses. Results Mean survival time was 105.6 months in patients with ccRCC. Patients with high expression of VEGF, HIF-1α and HIF-2α positivity, a high Ki-67 proliferation index, and a high microvessel density evaluation score had a shorter survival time (p<0.05). Conclusions Our findings supported that with the use of these immunohistochemical markers, prognosis of renal cell carcinoma may be predicted at the first step of patient management. New treatment modalities targeted to HIF-1α and HIF-2α might be planned as well as VEGF-targeted therapies in the management of clear cell renal cell carcinomas
Comparison of clinicopathological features in incidental and nonincidental papillary thyroid carcinomas in 308 patients
Incidental papillary thyroid carcinomas (IPTCs) consist of a significant portion of increasing incidence in papillary thyroid carcinomas. This study investigated the clinicopathological features of IPTCs from different perspectives and by comparing nonincidental PTCs (NIPTCs) in patients who underwent total thyroidectomy and lymph node dissection. Basic results were as follows. IPTC was present in 27.9% of 308 patients. IPTCs were significantly accompanied by lymphocytic thyroiditis (LT), particularly, multinodular hyperplasia (MNH). IPTCs were more common in older patients (51.3 years vs. 47.2 years) and in female patients. IPTCs significantly differed from NIPTCs in terms of smaller tumour size, lymphatic vessel invasion (2.6% vs. 97.4%), extrathyroidal extension (4.3% vs. 95.7%), lymph node metastasis (3.6% vs. 96.4%), multifocality (21.2% vs. 78.8%), bilaterality (5.3% vs. 94.7%), and BRAFV600 mutation (6.7% vs. 93.3%). Older age, bilaterality, encapsulation, and radioactive iodine (RAI) were significantly more common in IPTCs > 5 mm than in those ≤ 5 mm. In conclusion, IPTCs are more commonly associated with LT and MNH. IPTCs may have a more favourable prognosis than NIPTCs, and tumour size > 5 mm may predict bilaterality and need for RAI. Nevertheless, the patient-based clinical approach in IPTCs may have benefits in the management of IPTCs
Histological perspective on the effects of tumor-associated macrophages in the tumor microenvironment surrounding papillary thyroid carcinoma
Tumor-associated macrophages (TAMs) are one of the most noticeable elements of the tumor microenvironment. The present study investigated the relationships between the density of CD163 immunolabeled M2-like TAMs with other histological properties of the tumor microenvironment and clinipathological features in 90 patients with papillary thyroid carcinomas (PTC). The percentage of TAMs was higher in tumors with significant lymphocytic tumor response (p = 0.020), in tumors with a significant degree of stromal tumor response (p = 0.014), those with infiltrative tumor borders (p = 0.029), in conventional variant papillary carcinoma (p = 0.032), and in patients with autoantibodies for thyroid peroxidase (p = 0.014). The tumors associated with lymphocytic thyroiditis had lower numbers of TAMs (p = 0.027). In conclusion, for the first time, the present study attempts to establish a full assessment of interactions of CD163 expressing M2-like TAMs with the triad of primary tumor- tumor microenvironment- tumor behavior and above all, with markers of autoimmunity. Thus, these alternatively polarized macrophages may act in tumor progression and dissemination according to their various products, which may be ordered by tumor cells or neighboring immune cells. The molecular studies may reveal their roles in various tumors and may improve the therapy strategies targeting TAMs in various malignant tumors, including PTCs
Follicular morphological characteristics may be associated with invasion in follicular thyroid neoplasms with papillary-like nuclear features
The newly proposed nomenclature and diagnostic criteria for encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC), the noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), could improve the consistency and accuracy of diagnosing this entity. Diagnosis of NIFTP requires evaluation of the complete tumor border or capsule. The presence of tumor invasion in follicular thyroid neoplasms with papillary-like nuclear features has been recently discussed by many authors. In this study, we examined the predictive value and association of follicular morphological characteristics with the tumor invasion. In addition, we analyzed the association between tumor encapsulation and molecular profile in EFVPTC/NIFTP cases. A total of 106 cases of FVPTC were included in the study. The tumors were grouped based on the presence of tumor capsule and characteristics of tumor border, as 1) completely encapsulated tumors without invasion, 2) encapsulated tumors with invasion, 3) infiltrative tumors without a capsule. Clinicopathological features, histomorphological features [nuclear criteria, minor diagnostic features, follicles oriented perpendicular to tumor border/capsule (FOPBC)] and molecular alterations in BRAF, NRAS, and KRAS genes were evaluated. FOPBC were significantly more frequently seen in encapsulated tumors with invasion (p = 0.008). The nuclear features were not associated with the presence of encapsulation and characteristics of tumor border. BRAF mutation was more frequent in infiltrative tumors, while NRAS mutation was more frequent in encapsulated tumors, but the results were not statistically significant (p = 0.917). In conclusion, FOPBC histomorphological feature may be associated with tumor invasion in EFVPTC/NIFTP. Additionally, BRAF/KRAS/NRAS mutation analysis may prevent inadequate treatment in these patients
Impact of next‐generation sequencing panels in the evaluation of limb‐girdle muscular dystrophies
Introduction Limb-girdle muscular dystrophy (LGMD) is the fourth most common muscular dystrophy, with progressive proximal muscle weakness. However, a large number of neuromuscular conditions are similarly presented. Because of this, the use of high-throughput methods such as next-generation sequencing (NGS) is important in the evaluation of LGMD. Methods In this report, we applied a custom target capture-based NGS panel covering 31 LGMD-associated genes (MYOT, LMNA, CAV3, DES, DNAJB6, FLNC, CAPN3, DYSF, SGCG, SGCA, SGCB, SGCD, TCAP, TRIM32, FRKP, TTN, POMT1, ANO5, FKTN, POMT2, POMGnT1, DAG1, PLEC, GAA, GMPPB, HNRNPDL, TNPO3, LIMS2, POMK, TRAPPC11, ISPD) in 74 patients suspected of LGMD. Results In 25 (33.8%) out of 74 patients analyzed, one or more pathogenic/likely pathogenic variants in 13 different genes were detected. Six of the patients had the variants that were not found in databases and literature; thus, they were interpreted as novel pathogenic variants. Discussion The diagnosis rate achieved (33.8%) is consistent with previous literature reports and underlines the efficiency and importance of NGS technology in the molecular genetic evaluation of LGMD
Impact of next-generation sequencing panels in the evaluation of limb-girdle muscular dystrophies
Introduction Limb-girdle muscular dystrophy (LGMD) is the fourth most common muscular dystrophy, with progressive proximal muscle weakness. However, a large number of neuromuscular conditions are similarly presented. Because of this, the use of high-throughput methods such as next-generation sequencing (NGS) is important in the evaluation of LGMD. Methods In this report, we applied a custom target capture-based NGS panel covering 31 LGMD-associated genes (MYOT, LMNA, CAV3, DES, DNAJB6, FLNC, CAPN3, DYSF, SGCG, SGCA, SGCB, SGCD, TCAP, TRIM32, FRKP, TTN, POMT1, ANO5, FKTN, POMT2, POMGnT1, DAG1, PLEC, GAA, GMPPB, HNRNPDL, TNPO3, LIMS2, POMK, TRAPPC11, ISPD) in 74 patients suspected of LGMD. Results In 25 (33.8%) out of 74 patients analyzed, one or more pathogenic/likely pathogenic variants in 13 different genes were detected. Six of the patients had the variants that were not found in databases and literature; thus, they were interpreted as novel pathogenic variants. Discussion The diagnosis rate achieved (33.8%) is consistent with previous literature reports and underlines the efficiency and importance of NGS technology in the molecular genetic evaluation of LGMD